docs: def _add_nic_to_mapping(self, net, dom, nic):
          """
          Populates the given net spec mapping entry with the nics of the given
          domain, by the following rules:
  
              * If ``net`` is management, 'domain_name': nic_ip
              * For each interface: 'domain_name-eth#': nic_ip, where # is the
              index of the nic in the *domain* definition.
              * For each interface: 'domain_name-net_name-#': nic_ip,
              where # is a running number of interfaces from that network.
              * For each interface: 'domain_name-net_name', which has an
              identical IP to 'domain_name-net_name-0'
  
  
          Args:
              net (dict): Network spec to populate
              dom (dict): libvirt domain specification
              nic (str): Name of the interface to add to the net mapping from the
                  domain
  
          Returns:
              None
          """
          dom_name = dom['name']
          idx = dom['nics'].index(nic)
          name = '{0}-eth{1}'.format(dom_name, idx)
          net['mapping'][name] = nic['ip']
          if dom['nics'][idx]['net'] == dom['mgmt_net']:
              net['mapping'][dom_name] = nic['ip']
  
          name_by_net = '{0}-{1}'.format(dom_name, nic['net'])
          named_nets = sorted(
              [
                  net_name for net_name in net['mapping'].keys()
                  if net_name.startswith(name_by_net) and net_name != name_by_net
              ]
          )
  
          if len(named_nets) == 0:
              named_idx = 0
              net['mapping'][name_by_net] = nic['ip']
          else:
              named_idx = len(named_nets)
          named_net = '{0}-{1}'.format(name_by_net, named_idx)
  
          net['mapping'][named_net] = nic['ip']